Isoniazid, also known as isonicotinylhydrazide (INH), is an antibiotic used for the treatment of tuberculosis. For latent tuberculosis it is often used by itself. It is unclear if use during pregnancy is safe for the baby. Pyridoxine may be given to reduce the risk of side effects. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. Isoniazid is available as a generic medication. In the United States a month of treatment costs less than $25.